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American Kestrel
The American Kestrel (Falco sparverius), is the smallest falcon in North America. Description American Kestrels have a black double "mustache". The males' wings are gray and the females' are brown with darker barring. The male's nape is tawny with a black spot and has a red-brown tail and spot on its crown. American Kestrels are 8.7-12.2 inches (22-31 centimeters) in length, weigh 2.8-5.8 ounces (80-165 grams), and have a wingspan of 20.1-24.0 inches (51-61 centimeters). Occurrence American Kestrels favor open areas with short and sparse ground vegetation. The southeastern U.S. form breeds in unusual longleaf pine sandhill habitat. When breeding, kestrels need access to at least a few trees or structures that provide appropriate nesting cavities. American Kestrels are attracted to many habitats modified by humans, including pastures and parkland, and are often found near areas of human activity including towns and cities. American Kestrels can be found all over America except for the northernmost and Amazon Rain forest areas. They are resident to long-distance migrants. In North America, the tendency for kestrels to migrate decreases from north to south, with southernmost populations resident year-round. While some American Kestrels migrate to Central America, the great majority spend the winter in the southern United States. Kestrels are a common sight along mountain ridges and at hawk watches during fall migration. Life History Diet This bird eats small animals; mostly insects and rodents as well as small birds. They may also snack on larger birds and reptiles. Nesting American Kestrels nest in cavities, although they lack the ability to excavate their own. The male searches for possible nest cavities. When he’s found suitable candidates, he shows them to the female, who makes the final choice. They nest readily in human-erected nest boxes. American Kestrels do not use nesting materials. If the cavity floor is composed of loose material, the female hollows out a shallow depression there. They lay 4-5 eggs per clutch. Kestrels only lay 1-2 broods per year. The eggs are 1.2-1.5 inches (3-3.8 centimeters) in length and 0.9-1.1 inches (2.4-2.8 centimeters) in width. Incubation period is 26-32 days and nestling period is 28-31 days for these small falcons. The eggs are white to yellowish or light reddish-brown, mottled with violet-magenta, gray, or brown. The hatchlings are feeble, with sparse white down over pinkish skin; their eyes partially open by first or second day. Behavior American Kestrels normally hunt by day. Kestrels can often be spotted scanning for prey from the same perch all day long—or changing perches every few minutes. A kestrel pounces on its prey, seizing it with one or both feet; the bird may finish off a small meal right there on the ground, or carry larger prey back to a perch. During breeding season, males advertise their territory by repeatedly climbing and then diving, uttering a short series of klee! calls at the top of each ascent. Courting pairs may exchange gifts of food; usually the male feeds the female. Early in the pairing-up process, groups of four or five birds may congregate. American Kestrels may harass larger raptors during migration, and attacking hawks in their territories during breeding season. Kestrels compete over the limited supply of nesting cavities with other cavity-nesters, and sometimes successfully fight off or evict other competitors from their chosen sites. Conservation The American Kestrel is the continent’s most common and widespread falcon but populations declined by about 50% between 1966 and 2015, according to the North American Breeding Bird Survey. Partners in Flight estimates the global breeding population at 4 million, with 39% spending some part of the year in the U.S., 10% in Mexico, and 13% breeding in Canada. They rate an 11 out of 20 on the Continental Concern Score and are not on the 2016 State of North America's Birds' Watch List. Current declines stem from continued clearing of land and felling of the standing dead trees these birds depend on for their nest sites. The American Kestrel is also losing prey sources and nesting cavities to “clean” farming practices, which remove suitable vegetation. An additional threat is exposure to pesticides and other pollutants, which can reduce clutch sizes and hatching success. For kestrels in North America, a larger problem with pesticides is that they destroy prey on which the birds depend. Gallery American Kestrel.jpg|Female (northern) American kestrel.jpg|Adult male (northern) in flight. Cuban American Kestrel.jpg|Adult male (Cuban) Americankestrel.jpg|Female (Cuban) Borb Attempt.jpg|Adult male (northern) Kestrel and Flicker.jpg|Northern Flicker and adult male American Kestrel disbuting over perching rights.|link=Northern Flicker Splendid Kestrel.jpg|Adult male landing. Trivia * The American Kestrel is shrinking in body size. The reason currently unknown and is being investigated by scientists. * Sports fans in some cities get an extra show during night games: kestrels catching snacks on the wing. Some of their hunting flights have even made it onto TV sports coverage. * Unlike humans, birds can see ultraviolet light. This enables kestrels to make out the trails of urine that voles, a common prey mammal, leave as they run along the ground. Like neon diner signs, these bright paths may highlight the way to a meal. * American Kestrels hide surplus kills in grass clumps, tree roots, bushes, fence posts, tree limbs, and cavities, to save the food for lean times or to hide it from thieves. * The oldest American Kestrel was a male and at least 14 years, 8 months old when he was found in Utah in 2001. He had been banded in the same state in 1987. Category:Birds Category:Birds of prey Category:Falconiformes Category:Falconidae Category:Birds of North America Category:Birds of the United States Category:Bird Species Category:Falco Category:Aves